Q. For a solution containing 2 components A and B, if the mole fraction of A is 0.6, what is the vapor pressure of the solution if the vapor pressure of pure A is 100 mmHg?
A.
60 mmHg
B.
100 mmHg
C.
40 mmHg
D.
80 mmHg
Solution
According to Raoult's Law, the vapor pressure of the solution is P_A = X_A * P_A^0 = 0.6 * 100 mmHg = 60 mmHg.
Q. For an ideal solution, if the mole fraction of the solvent is 0.75, what is the vapor pressure of the solution if the vapor pressure of the pure solvent is 100 mmHg?
A.
75 mmHg
B.
100 mmHg
C.
25 mmHg
D.
50 mmHg
Solution
According to Raoult's Law, the vapor pressure of the solution is 0.75 * 100 mmHg = 75 mmHg.
Q. If a solution has a vapor pressure of 80 mmHg and the pure solvent has a vapor pressure of 100 mmHg, what is the mole fraction of the solvent?
A.
0.8
B.
0.75
C.
0.6
D.
0.5
Solution
Using Raoult's Law, the mole fraction of the solvent can be calculated as 80 mmHg / 100 mmHg = 0.8, which corresponds to a mole fraction of 0.75 for the solvent.
Q. If the vapor pressure of a pure solvent is 80 mmHg and a non-volatile solute is added, resulting in a vapor pressure of 60 mmHg, what is the mole fraction of the solvent in the solution?
Q. If the vapor pressure of a solution is 80 mmHg and the vapor pressure of the pure solvent is 120 mmHg, what is the mole fraction of the solvent in the solution?
Q. If the vapor pressure of pure solvent A is 100 mmHg, and the mole fraction of A in the solution is 0.6, what is the vapor pressure of the solution according to Raoult's Law?
Q. If the vapor pressure of pure solvent A is 100 mmHg, and the mole fraction of A in the solution is 0.5, what is the vapor pressure of the solution according to Raoult's Law?
A.
50 mmHg
B.
100 mmHg
C.
150 mmHg
D.
200 mmHg
Solution
According to Raoult's Law, P_solution = X_A * P_A^0 = 0.5 * 100 mmHg = 50 mmHg.
Q. If the vapor pressure of pure solvent is 120 mmHg, what will be the vapor pressure of a solution containing 0.2 moles of solute in 1 mole of solvent?
A.
100 mmHg
B.
110 mmHg
C.
120 mmHg
D.
80 mmHg
Solution
Using Raoult's Law, the vapor pressure of the solution is P_solution = P_solvent * X_solvent = 120 * (1/(1+0.2)) = 120 * (1/1.2) = 100 mmHg.
Q. If the vapor pressure of pure solvent is 80 mmHg and the mole fraction of the solvent in the solution is 0.75, what is the vapor pressure of the solution?
Q. In a binary solution of A and B, if the vapor pressure of A is 80 mmHg and that of B is 40 mmHg, what is the total vapor pressure when both are present?
A.
40 mmHg
B.
80 mmHg
C.
120 mmHg
D.
100 mmHg
Solution
The total vapor pressure is the sum of the partial pressures: P_total = P_A + P_B = 80 mmHg + 40 mmHg = 120 mmHg.
Q. In a binary solution of A and B, if the vapor pressure of A is 80 mmHg and that of B is 40 mmHg, what is the total vapor pressure of the solution if the mole fraction of A is 0.75?
Q. In a binary solution of A and B, if the vapor pressure of pure A is 150 mmHg and pure B is 50 mmHg, what is the total vapor pressure when the mole fraction of A is 0.4?
Q. In a binary solution of A and B, if the vapor pressure of pure A is 80 mmHg and pure B is 40 mmHg, what is the vapor pressure of the solution if the mole fraction of A is 0.6?
A.
64 mmHg
B.
72 mmHg
C.
80 mmHg
D.
56 mmHg
Solution
Using Raoult's Law, the vapor pressure of the solution = (0.6 * 80 mmHg) + (0.4 * 40 mmHg) = 64 mmHg.
Q. In a binary solution of A and B, if the vapor pressure of pure A is 80 mmHg and pure B is 40 mmHg, what is the vapor pressure of component A if the mole fraction of A is 0.6?
A.
48 mmHg
B.
64 mmHg
C.
80 mmHg
D.
32 mmHg
Solution
Using Raoult's Law, the vapor pressure of A in the solution is 0.6 * 80 mmHg = 48 mmHg.
Q. In a binary solution of A and B, if the vapor pressure of pure A is 80 mmHg and that of pure B is 40 mmHg, what is the total vapor pressure when the mole fraction of A is 0.6?
A.
64 mmHg
B.
72 mmHg
C.
80 mmHg
D.
88 mmHg
Solution
Using Raoult's Law, the total vapor pressure = (0.6 * 80 mmHg) + (0.4 * 40 mmHg) = 48 mmHg + 16 mmHg = 64 mmHg.
Q. In a binary solution of A and B, if the vapor pressure of pure A is 80 mmHg and pure B is 40 mmHg, what is the total vapor pressure when the mole fraction of A is 0.5?
Q. In a binary solution of A and B, if the vapor pressure of pure A is 80 mmHg and that of pure B is 40 mmHg, what is the vapor pressure of the solution if the mole fraction of A is 0.6?
A.
64 mmHg
B.
72 mmHg
C.
80 mmHg
D.
56 mmHg
Solution
Using Raoult's Law, the vapor pressure of the solution = (0.6 * 80 mmHg) + (0.4 * 40 mmHg) = 64 mmHg.
Q. In a solution of two volatile components A and B, if the mole fraction of A is 0.6, what is the vapor pressure of the solution if the vapor pressure of pure A is 100 mmHg and that of pure B is 50 mmHg?
A.
80 mmHg
B.
90 mmHg
C.
70 mmHg
D.
60 mmHg
Solution
Using Raoult's Law, the vapor pressure of the solution is P_total = (0.6 * 100) + (0.4 * 50) = 60 + 20 = 80 mmHg.
Raoults Law is a fundamental concept in chemistry that plays a crucial role in understanding solutions and their properties. Mastering this law is essential for students preparing for school exams and competitive tests. Practicing MCQs and objective questions on Raoults Law not only enhances your conceptual clarity but also boosts your confidence in tackling important questions during exams.
What You Will Practise Here
Definition and significance of Raoults Law
Application of Raoults Law in ideal solutions
Calculating vapor pressure using Raoults Law
Understanding the concept of mole fraction
Real-life applications and examples of Raoults Law
Common misconceptions related to Raoults Law
Practice questions and solved examples for better understanding
Exam Relevance
Raoults Law is frequently featured in various examinations, including CBSE, State Boards, NEET, and JEE. Students can expect questions that require them to apply the law to solve numerical problems or explain its significance in the context of solutions. Common question patterns include direct applications of the law, calculations involving vapor pressure, and conceptual questions that test understanding of ideal and non-ideal solutions.
Common Mistakes Students Make
Confusing Raoults Law with Henry's Law
Misunderstanding the concept of ideal solutions
Incorrectly calculating mole fractions
Overlooking the significance of temperature in vapor pressure
Failing to apply the law to real-world scenarios
FAQs
Question: What is Raoults Law? Answer: Raoults Law states that the vapor pressure of a solvent in a solution is directly proportional to the mole fraction of the solvent in the solution.
Question: How is Raoults Law applied in calculations? Answer: It is used to determine the vapor pressure of a solvent when mixed with a solute, allowing for calculations based on mole fractions.
To excel in your exams, it is vital to solve practice MCQs on Raoults Law and test your understanding. Embrace the challenge and enhance your preparation by tackling these important Raoults Law questions today!
Soulshift Feedback×
On a scale of 0–10, how likely are you to recommend
The Soulshift Academy?
